Ratchet wrench with hydraulically operated lock



Sept. 16, 1969 M. J. GEGG RATCHET WRENCH WITH HYDRAULIGALLY OPERATED LOCK Filed March 17, 1967 INVENTOR MiCHAEL J 6566 United States Patent 3,466,953 RATCHET WRENCH WITH HYDRAULICALLY OPERATED LOCK Michael J. Gegg, 591 Soniat Ave., Harahan, La. 70123 Filed Mar. 17, 1967, Ser. No. 623,951 Int. Cl. B25b 13/46 US. Cl. 8158.3 3 Claims ABSTRACT OF THE DISCLOSURE The present invention relates to a novel ratchet lever that finds diverse application in the tool and related arts. More particularly, the present ratchet lever is especially concerned with ratchet levers adapted for use as wrenches.

The tool art is replete with ratchet wrenches comprising a lever portion containing a ratchet mechanism whereby the lever portion can be rotated without removal of the wrench head or socket from the engaged nut or bolt. This is accomplished, as for example in the wrench shown in US. Patent 2,708,855, by simply reciprocating the handle back and forth.

Present day wrenches are characteristically designed such that they do not have an idle position. That is, the handle is always in an engaging condition and it must be rotated sufficiently to allow the pawl to engage the next tooth. This mode of operation presents certain disadvantages which are overcome by the instant invention.

The primary object of this invention is to provide an exceptionally strong ratchet wrench having a ratchet mechanism that is always in an idle non-engaging condition, but which, however, can be rapidly and easily actuated by the user.

The present invention basically comprises a ratchet mechanism that is actuated by hydraulic pressure applied by the grip of the user to the Wrench handle during its normal operation.

BACKGROUND OF THE INVENTION The present invention pertains to that field of art as embraced, inter alia, in Class 81, subclass 61, which is broadly concerned with ratchet wrenches adapted for use as a socket wrench or similar ratchet tool. Most of the ratchet lever wrenches on the market today comprise a basic design that is old in the art, e.g., see US. Patent 841,831. The mode of operation of the ratchet wrench shown in that patent is substantially the same in present day ratchet wrenches. Namely, the ratchet comprises an inner member having circumferential teeth which are brought into contact with a pawl that is urged into operable position therewith by virtue of a spring. Various improvements have been made through the years in the exact position of the pawl, the number of pawls, and the structural design from a strength viewpoint so as to reduce the over-all size of the head of the wrench to allow it to be used in close quarters. Additionally, many of the present day improvements have been directed to making reversible Wrenches.

As brought out above, ratchet wrenches sold today are not specifically designed to allow the handle to move back and forth in a non-engaging or idling motion. This condition results in distinct disadvantage in many instances. For example, where the handle of a wrench has been allowed to move back to a position where it cannot be, grabbed or held securely it thereby becomes necessary to lift the wrench from the work piece and replace it in the desired position. This is easier said than done because quite often the wrench has been fitted into Patented Sept. 16., 1969 a very tight confining location which does not allow it to be easily removed. In the case of a wrench that has a reversing mechanism, while the wrench need not be removed from the work piece, it is necessary to flip the reversing mechanism and move the handle to the desired position and thereafter flip the reversing mechanism to its former position. In both instances, the net result is lost motion.

Another disadvantage of present day ratchet wrenches comes into play in the process of tightening a nut that is not yet tight enough to allow the wrench to be ratcheted backwards without the nut rotating, yet the nut being too tight for removal by hand. In such an instance, it becomes necessary to employ a conventional open end or box wrench to rotate the nut.

Yet another disadvantage of ratchet wrenches today is the necessity of having to move the handle of the wrench through .a sizable arc in order to engage the adjacent ratchet tooth. This are of actuation is prescribed by the relative spacing of the ratchet teeth. Admittedly, this problem can be minimized by spacing the ratchet teeth very close together. However, to do so weakens the wrench as well as reduces its wearability.

SUMMARY The above and other problems of present day ratchet wrenches are overcome in an eflicacious manner by the present ratchet wrench which comprises a ratchet mechanism that is actuated by hydraulics. The pawl that engages the teeth which are operably connected to the work piece is actuated by a hydraulic force that is generated by the user of the wrench upon gripping the handle. The handle comprises hydraulic piston means which are actuated upmn gripping the handle of the wrench as brought out above. Thus, when the piston means are not under compression, the handle of the wrench is in an idle or nonengaging condition whereby it can be readily moved backwards or forwards to any position and actuated as desired. In this manner, the prior art problems associated with present day ratchet wrenches are easily avoided without any sacrifice of strength. In fact, the instant wrench can absorb a greater torque than similar size present day wrenches.

BRIEF DESCRIPTION OF THE DRAWING FIGURE 1 depicts an exploded isometric view of the present hydraulic ratchet wrench.

FIGURE 2 represents a sectional view taken along the line AA of FIGURE 1.

FIGURE 3 represents a partial sectional view of the handle of the present wrench taken along the plane prescribed by the line B-B of FIGURE 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT The present hydraulic ratchet wrench comprises the main lever frame 10 which further comprises the lever head 11, the shank portion 12, and the handle portion 13. Nestled within the lever head 11 is the hydraulic ratchet mechanism means 14. The ratchet mechanism means 14 further comprises the pawl retaining block 15. The member 15 is cup shaped so as to define the cavity 16 on its bottom side as indicated by the dashed lines. Adapted for fitting within the cavity 16 is the hydraulic piston 17 which functions in the manner described in detail hereinafter.

The member 15 is also provided with one or more of the chambers 18 into which a ratchet pawl 19 is operably positioned. The chamber 18 is further defined as having the extended lips or portions 20 and 21. Each pawl is provided with the extensions 22 along each side thereof. The portions 20 and 21 are spaced suflicient to accommodate the pawl 19, yet insufficient to allow the pawl 19 to pass entirely out of the chamber 18 by virtue of the extensions 22 which come into contact with the portions 20 and 21 when the tooth is in a fully extended vertical position. The spring 23 is provided for urging the pawl 19 vertically upwards at all times for the reason brought out hereinafter. The spring 23 is positioned within the chamber '18 between the bottom thereof and the bottom of the pawl 19.

The lever head 11 is provided with the grooves 24 which are of sufficient circumferential width to receive the outer vertical portion of the pawl 19, e.g., that portion of the pawl represented by the termination of the extensions 22. The lever head 11 is bored to receive the ratchet mechanism 14, specifically, the block being of a diameter suflicient to fit within the annulus 25.

The lever head 11 is further bored to provide the inner annulus or hydraulic cylinder portion 26 which is of a diameter sufiicient to receive the hydraulic piston 17 and of a depth sufiicient to provide for its vertical displacement when lifting the member 14. The cylindrical walls of the portion 26 protrude upwards and extend in the cavity provided within the member 15. This structural relationship is not critical, however, it is preferred since it minimizes the thickness of the head portion. The piston 17 is mounted within the annulus 26 and functions in the manner described hereinafter.

The spring 27 is provided between the member 15 and the ratchet tooth reel 28. The member 28 is provided with a series of teeth or extensions 29 which extend circumferentially around the reel 28. The teeth 29 are spaced sufficiently apart so as to allow the pawls 19 to project upwards therebetween and thus engage a respective tooth 29. The reel 28 is also provided with the extension 30 which is of a diameter sufiicient to fit within the outermost annulus 31 of the lever head 11. The outer diameter of the teeth 29 is sufficient such that the reel 28 rotatably fits within the annulus 25 of the head 11. The reel 28 is further provided with the circular portion 31 and the extension 32 to which is operably fastened the particular tool to be operated by the present ratchet lever. Preferably, the extension 32 is a square shaped extension adapted to mate with a conventional socket, however, the extension 32 rould comprise any shape or configuration for connecting to whatever tool or item desired.

The retaining plate 33 is provided for retaining the ratchet mechanism within the lever head 11. The plate 33 is of a diameter suflicient to mate with the lever head 11 and is provided with suitable means for attaching thereto, e.g., by virtue of screws or rivets extending through the holes 34 of the plate 33 which correspond to the holes 35 of the head 11. The plate 33 is further characterized as having the inner hole 36 which is of a diameter sufiicient to receive the circular top portion of the reel 28. By such means, the ratchet reel 28 and the other components of the ratchet mechanism are rotatably retained within the lever head 11.

The ratchet mechanism is actuated by hydraulic pressure by virtue of a reservoir of hydraulic fluid contained within the chamber 40 that extends lengthwise through the entire lever 10. The chamber 40 is in open communication with the annulus 26 whereby fluid pressure can be exerted upon the bottom of the piston 17. The chamber 40 terminates within the handle portion 13 in open communication with the hydraulic piston chamber 41. The chamber 41 is a circular hole provided within the handle portion 13, the longitudinal axis of which is perpendicular to that of the chamber 40. The hydraulic pistons 42 and 43 are positioned within the chamber 41 for pressurizing the hydraulic fluid therein. The pistons 42 and 43 are sealed within the chamber 41 by virtue of the O-rings 44 and 45 respectively.

The piston compressing means 46 and 47 are nestled within the handle portion 13 whereby upon being squeezed .4 by the hand of the user, the piston 42 and 43 respectively are caused to act upon the fluid in the chamber 41. The handle 13 is provided with the slots 48 and 49 which receive the means 46 and 47 respectively. These slots are in turn provided with the notched portions 50 and 51 at one end and 52 and 53 at the other end. The piston compressing means are inserted and retained within the slots, for example, by first inserting one end of the means 46 into the groove 52 and thereafter sliding it forward such that its other end comes into position within the groove 50. Thereafter, the pins 54 and 55 are inserted for preventing the means 46 and 47 respectively from sliding backwards and falling out. The leaf springs 56 and 57 are provided for urging the means 46 and 47 respectively alway outwards such that upon release of the handle, the ratchet mechanism within the head of the wrench is disengaged.

The hydraulic reservoir within the wrench is filled by virtue of the port 58 which opens into the expanded chamber portion 59. The threaded plug 60 is provided for closing off the hydraulic reservoir.

The handle is provided with such refinements as the dished portions 61 and the rubber strips 62 to provide positive gripping of the wrench.

In operation, the wrench is placed on a work piece which is thereafter rotated or worked upon by the user upon gripping and compressing the members 46 and 47 inwards. The piston compression means in turn act upon the pistons 42 and 43 respectively whereby fluid within the chamber or reservoir 41 is placed under pressure. This hydraulic pressure generated is transmitted through the fluid in the chamber 40 ultimately into the lever head portion 11 where it acts upon the bottom side of the piston 17. This causes the piston 17 to move upwards counteracting the downward force imparted by the spring 27. When the reel 28 is actuated, the pawls 19 that do not find any empty space are consequently shoved downwards in their respective chambers. Where none of the pawls find an empty slot, then due to the pressure of the spring 27, upon rotating the wrench a position will be realized whereby one of the pawls 19 will come into alignment with an empty space defined within the teeth 29 of the reel 28. When this occurs, that pawl immediately moves upwards by virtue of the spring 23. The pawl thereupon engages a tooth 29 whereby the ratchet reel 28 is rotated and the work piece is worked upon.

The angular position of the pawls 19 can be set such that all of the pawls come into play on a power stroke. That is, the chambers 18 can be positioned such that all of the pawls move upwards into the openings defined between the teeth 29. However, it is preferred to space the pawls 19 such that only one pawl comes into play because this is generally all that is required to carry the load. In such an arrangement, the preferred angular displacement of all of the pawls is such that the pawls would engage a tooth upon rotation of the wrench through an arcuate path defined by the length of the radial are prescribed bythe diameters of adjacent teeth. In such manner, it is not necessary as in conventional ratchet wrenches to rotate the handle of the Wrench through at least the are prescribed by the center lines of adjacent teeth since there is more than one pawl in the present wrench, preferably fourjwhich are circumferentially positioned such that the angular position of each pawl is different. In the case of the preferred embodiment of the present invention employing four pawls, what this means is that the pawls are not positioned on common perpendicular center lines. Rather, the pawls would be positioned, for example, on angles of 88, 89, 91 and 92 degrees. This angular differential, indicated by the angle X in FIGURE 1, is roughly obtained by dividing the angular difference or the included angle between adjacent teeth by the number of pawls minus one.

The incremental angle thus realized is then employed to determine the included angle X between adjacent awls.

P In light of the foregoing description, it will be apparent to one skilled in the art that various modifications can be made in the present hydraulic ratchet wrench without departing from the true scope and spirit of this invention. For example, the particular means by which the hydraulic pistons within the handle 13 are compressed can vary in shape and number. Moreover, the exact position and number of hydraulic pistons within the handle can be varied. Other modifications to that depicted in the drawing which is illustrative of my invention will be apparent to one skilled in the art. What I expressly desire to cover by United States Letters of Patent is that set forth in the appended claims.

I claim:

1. A hydraulic ratchet lever comprising:

(a) Lever means having head and handle portions which define hydraulic piston chambers therein which are in open communication with each other;

(b) Ratchet means operably positioned within said head portion which ratchet means further comprises at least one pall means adapted to slidably fit within said head portion whereby it can travel in a direction perpendicular to the longitudinal axis of said head portion, and ratchet tooth means operably connected to a work piece and rotatably positioned within said head portion with respect to said pall means whereby said means are engaged upon actuation of said pall means as hereinafter described;

(c) A first hydraulic means operably positioned within said head portion which means further comprises a hydraulic piston operably connected to said pall means for actuation thereof, said hydraulic piston being adapted for travel in a direction perpendicular to the longitudinal axis of said head portion whereby said pall means and said ratchet tooth means can thereby be operably engaged; and

(d) A second hydraulic means operably positioned within said handle portion for actuating said first hydraulic means.

2. The hydraulic ratchet level of claim 1 further characterized in that:

the head and handle portions of said lever means (a) are further characterized as defining hydraulic piston chambers therein which are in open communication with each other; the piston chamber provided within said handle portion having its longitudinal axis essentially perpendicular to that of said lever means (a); said head portion being further defined in that at least one groove is provided in the peripheral wall defined by the piston chamber therein, the longitudinal axis of the groove extending perpendicular to said lever means (a);

said ratchet means (b) comprises:

(1) At least one pawl means having extensions along its bottom side and one side adapted to slidably fit within the groove provided within said head portion;

(2) Pawl retaining means having at least one pawl retaining chamber therein wherein said pawl means is slidably positioned, the chamber having a narrowed portion at the top thereof whereby said pawl means is vertically restricted therein; the chamber and the groove provided in said head portion being operably positioned with respect to each other such that said pawl retaining means and said pawl means when operably positioned within said head portion are prevented from rotation but are free to move relative to each other along their common longitudinal axis;

(3) Resilient means positioned between said pawl retaining means (2) and said pawl means (1);

(4) Ratchet tooth means rotatably positioned with respect to said pawl means 1) whereby said means are engaged when said pawl retaining means (2) is actuated by said first hydraulic means (c); and

(5 Resilient means positioned between said ratchet tooth means (4) and said pawl retaining means (2) for urging the members apart when said first hydraulic means (0) is in a relaxed condition;

said first hydraulic means (c) comprises piston means operably positioned in the chamber provided in said head portion for actuating said ratchet means (b); and

said second hydraulic means (d) comprises handle piston means operably positioned within the chamber provided in said handle portion whereby hydraulic pressure can be applied to said first hydraulic piston means which in turn actuates said ratchet means.

3. The hydraulic ratchet lever of claim 1 further characterized in that;

the head and handle portions of said lever means (a) are further characterized as defining hydraulic pis ton chambers therein which are in open communication with each other; the piston chamber provided within said handle portion having its longitudinal axis essentially perpendicular to that of said lever means (a); said head portion being further defined in that four grooves are provided in the peripheral wall defined by the piston chamber therein, the longitudinal axes of the grooves extending perpendicular to said lever means (a); said handle portion also being further defined in that it is provided with two elongated grooves which extend lengthwise of said handle portion and which are in open communication with the chamber therein, the handle portion also being further defined as including indented portions at each end of the grooves, said handle portion also including an inlet port whereby the chamber provided therein can be filled with hydraulic fluid, and means for sealing the fluid therein;

said ratchet means (b) comprises;

(1) Four pawl means each having extensions along their bottom sides and one side adapted to slidably fit the grooves provided within said head portion;

(2) Pawl retaining means having four pawl retaining chambers therein in which said pawl means 1) are slidably positioned, each chamber having a narrowed portion at the top thereof whereby said pawl means 1) is vertically re stricted therein; the chambers and the grooves provided in said head portion being operably positioned with respect to each other such that said pawl retaining means and said pawl means (1) when operably positioned within said head portion are prevented from rotation but are free to move relative to each other along their common longitudinal axes; the chambers provided within said pawl retaining means being circumferentially spaced such that only one of said four pawl means (1) is operably engaged at any given time;

(3) Resilient means positioned between said pawl retaining means (2) and said pawl means (1);

(4) Ratchet tooth means rotatably positioned with respect to said pawl means (1) whereby said means are engaged when said pawl retaining means (2) is actuated by said first hydrau- 7 lic means (c); said ratchet tooth means being further defined as including a circular raised portion and a socket engaging portion;

() Means for retaining said ratchet means (b) within said head portion, said means being provided with a circular opening therein corresponding to the diameter of that of the raised portion of said ratchet tooth means (4) whereby the lateral position of said tooth means is fixed; and

(6) Resilient means positioned between said ratchet tooth means (4) and said pawl retaining means (2) for urging the members apart when said first hydraulic means (c) is in a relaxed position;

said first hydraulic means (c) comprises piston means operably positioned in the chamber provided in said head portion for actuating said ratchet (b); and said second hydraulic means (d) comprises;

(1) Handle piston means operably positioned within the chamber provided in said handle portion, said handle means being further defined as comprising two pistons positioned and sealed within such chamber;

MYRON c.

(2) Piston compression means for actuating said piston means 1) whereby hydraulic pressure can be applied to said head portion to actuate said ratchet means (b), said piston compression means being further defined in that they are adapted to fit within the grooves provided in said handle portion, said compression means also being provided with extensions at each end thereof for mounting within said handle portion;

(3) Means for retaining said compression means (2) within the grooves provided within said handle portion;

(4) Resilient means for urging said compression means (2) outwards when said compression means are in a relaxed condition thereby placing said lever means (a) in an idle condition.

References Cited UNITED STATES PATENTS KRUSE, Primary Examiner 

